/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Noto Sans JP', sans-serif;
    line-height: 1.7;
    color: #2d3748;
    background-color: #f7fafc;
    scroll-behavior: smooth;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Icons */
.icon {
    width: 24px;
    height: 24px;
    flex-shrink: 0;
}

/* Header */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #e2e8f0;
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: all 0.3s ease;
}

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 0;
}

.logo {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: #2563eb;
    font-weight: 600;
    font-size: 1.125rem;
    transition: all 0.3s ease;
}

.logo:hover {
    color: #1d4ed8;
    transform: translateY(-1px);
}

.logo .icon {
    margin-right: 0.5rem;
    width: 28px;
    height: 28px;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav-link {
    text-decoration: none;
    color: #4a5568;
    font-weight: 500;
    transition: all 0.3s ease;
    position: relative;
}

.nav-link:hover {
    color: #2563eb;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: #2563eb;
    transition: width 0.3s ease;
}

.nav-link:hover::after {
    width: 100%;
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    padding: 5rem 0;
    text-align: center;
    color: white;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="60" height="60" viewBox="0 0 60 60" xmlns="http://www.w3.org/2000/svg"><g fill="none" fill-rule="evenodd"><g fill="rgba(255,255,255,0.05)" fill-opacity="1"><circle cx="7" cy="7" r="7"/></g></g></svg>');
    opacity: 0.1;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    padding: 0.5rem 1rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border-radius: 50px;
    font-size: 0.875rem;
    font-weight: 500;
    margin-bottom: 1.5rem;
    border: 1px solid rgba(255, 255, 255, 0.3);
}

.hero-badge .icon {
    width: 16px;
    height: 16px;
    margin-right: 0.5rem;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1.5rem;
    line-height: 1.2;
}

.hero-description {
    font-size: 1.25rem;
    opacity: 0.9;
    max-width: 600px;
    margin: 0 auto;
}

/* Table of Contents */
.toc-section {
    padding: 3rem 0;
    background: white;
}

.toc-card {
    background: linear-gradient(135deg, #f0f9ff 0%, #e0f2fe 100%);
    border-radius: 1.5rem;
    padding: 2.5rem;
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
    border: 1px solid #bfdbfe;
}

.toc-title {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 600;
    color: #1e40af;
    margin-bottom: 1.5rem;
}

.toc-title .icon {
    margin-right: 0.75rem;
    color: #2563eb;
}

.toc-nav {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 0.75rem;
}

.toc-link {
    display: block;
    padding: 0.875rem 1.25rem;
    background: white;
    border-radius: 0.75rem;
    text-decoration: none;
    color: #374151;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 1px solid #e5e7eb;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.toc-link:hover {
    background: #2563eb;
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(37, 99, 235, 0.3);
}

/* Main Content */
.main {
    padding: 3rem 0;
}

.content-wrapper {
    max-width: 900px;
    margin: 0 auto;
}

/* Introduction Section */
.intro-section {
    margin-bottom: 3rem;
}

.intro-card {
    background: white;
    border-radius: 1rem;
    padding: 2.5rem;
    box-shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    border-left: 4px solid #2563eb;
}

.intro-text {
    font-size: 1.125rem;
    color: #4a5568;
    line-height: 1.8;
    font-weight: 500;
}

/* Policy Sections */
.policy-section {
    margin-bottom: 2rem;
    scroll-margin-top: 100px;
}

.section-card {
    background: white;
    border-radius: 1rem;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    border: 1px solid #e5e7eb;
    transition: all 0.3s ease;
}

.section-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
}

.section-title {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: 600;
    color: #1a202c;
    padding: 2rem 2rem 1rem;
    margin-bottom: 1rem;
}

.section-number {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 2.5rem;
    height: 2.5rem;
    background: linear-gradient(135deg, #2563eb 0%, #4f46e5 100%);
    color: white;
    border-radius: 50%;
    font-weight: 700;
    margin-right: 1rem;
    font-size: 1.125rem;
}

.section-content {
    padding: 0 2rem 2rem;
}

.section-content p {
    margin-bottom: 1.5rem;
    line-height: 1.8;
    color: #4a5568;
}

.section-content p:last-child {
    margin-bottom: 0;
}

/* Subsections */
.subsection {
    margin: 2rem 0;
    padding: 1.5rem;
    background: #f8fafc;
    border-radius: 0.75rem;
    border-left: 4px solid #3b82f6;
}

.subsection-title {
    display: flex;
    align-items: center;
    font-size: 1.125rem;
    font-weight: 600;
    color: #1e40af;
    margin-bottom: 1rem;
}

.subsection-title .icon {
    margin-right: 0.75rem;
    width: 20px;
    height: 20px;
}

.subsection p {
    color: #4a5568;
    margin-bottom: 1rem;
}

/* Link Boxes */
.link-box {
    background: #e0f2fe;
    border: 1px solid #0284c7;
    border-radius: 0.5rem;
    padding: 1rem;
    margin-top: 1rem;
}

.link-box p {
    margin-bottom: 0.5rem;
    color: #0c4a6e;
    font-weight: 500;
}

.external-link {
    display: inline-flex;
    align-items: center;
    color: #0284c7;
    text-decoration: none;
    font-weight: 500;
    word-break: break-all;
    transition: all 0.3s ease;
}

.external-link:hover {
    color: #0369a1;
    text-decoration: underline;
}

.external-link .icon {
    width: 16px;
    height: 16px;
    margin-left: 0.5rem;
    flex-shrink: 0;
}

/* Contact Info */
.contact-info {
    background: linear-gradient(135deg, #f0fdf4 0%, #dcfce7 100%);
    border: 1px solid #16a34a;
    border-radius: 0.75rem;
    padding: 2rem;
    margin-top: 1.5rem;
}

.contact-title {
    font-size: 1.125rem;
    font-weight: 600;
    color: #15803d;
    margin-bottom: 1rem;
}

.contact-details {
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.contact-item {
    display: flex;
    align-items: center;
    color: #166534;
    font-weight: 500;
}

.contact-item .icon {
    margin-right: 0.75rem;
    width: 20px;
    height: 20px;
    color: #16a34a;
}

/* Back to Top Button */
.back-to-top {
    position: fixed;
    bottom: 2rem;
    right: 2rem;
    width: 3rem;
    height: 3rem;
    background: linear-gradient(135deg, #2563eb 0%, #4f46e5 100%);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    box-shadow: 0 10px 25px rgba(37, 99, 235, 0.3);
    transition: all 0.3s ease;
    opacity: 0;
    visibility: hidden;
    z-index: 1000;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

.back-to-top:hover {
    transform: translateY(-2px);
    box-shadow: 0 20px 25px rgba(37, 99, 235, 0.4);
}

.back-to-top .icon {
    width: 20px;
    height: 20px;
}

/* Footer */
.footer {
    background: linear-gradient(135deg, #1f2937 0%, #374151 100%);
    color: white;
    padding: 3rem 0 1rem;
    margin-top: 4rem;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 2rem;
}

.footer-info {
    flex: 1;
}

.footer-logo {
    display: flex;
    align-items: center;
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
}

.footer-logo .icon {
    margin-right: 0.5rem;
    width: 28px;
    height: 28px;
    color: #60a5fa;
}

.footer-description {
    color: #9ca3af;
    font-size: 0.875rem;
}

.footer-nav {
    display: flex;
    gap: 2rem;
}

.footer-link {
    color: #d1d5db;
    text-decoration: none;
    font-weight: 500;
    transition: all 0.3s ease;
}

.footer-link:hover {
    color: #60a5fa;
}

.footer-bottom {
    border-top: 1px solid #4b5563;
    padding-top: 1rem;
    text-align: center;
}

.footer-bottom p {
    color: #9ca3af;
    font-size: 0.875rem;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeInUp 0.6s ease-out;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
    
    .nav {
        gap: 1rem;
    }
    
    .hero {
        padding: 3rem 0;
    }
    
    .hero-title {
        font-size: 2.5rem;
    }
    
    .hero-description {
        font-size: 1.125rem;
    }
    
    .toc-nav {
        grid-template-columns: 1fr;
    }
    
    .section-title {
        flex-direction: column;
        text-align: center;
        gap: 1rem;
        padding: 1.5rem 1.5rem 1rem;
    }
    
    .section-content {
        padding: 0 1.5rem 1.5rem;
    }
    
    .intro-card,
    .toc-card {
        padding: 2rem;
    }
    
    .subsection {
        padding: 1rem;
    }
    
    .contact-info {
        padding: 1.5rem;
    }
    
    .footer-content {
        flex-direction: column;
        gap: 2rem;
    }
    
    .footer-nav {
        flex-direction: column;
        gap: 1rem;
    }
    
    .back-to-top {
        bottom: 1rem;
        right: 1rem;
        width: 2.5rem;
        height: 2.5rem;
    }
    
    .back-to-top .icon {
        width: 18px;
        height: 18px;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }
    
    .section-title {
        font-size: 1.25rem;
    }
    
    .intro-card,
    .toc-card,
    .section-card {
        margin: 0 -8px;
        border-radius: 0.75rem;
    }
    
    .intro-card,
    .toc-card {
        padding: 1.5rem;
    }
    
    .section-content {
        padding: 0 1rem 1rem;
    }
    
    .section-title {
        padding: 1rem 1rem 0.5rem;
    }
}